I went shopping tonight prior to bringing my children to Chuck E Cheeses to wear themselves out and found a backpack sprayer at Home Depot. I know what youre thinking.......Home Depot Joe right? Well that's the only place that I know that would have something like that. Being a one man operation I plan on using it to prespray roofs while carrying something to rinse off the chemical; what are you guys opinions on the backpack sprayer with the Viton seals. I think it cost 80 bucks.